usb6.c

这是一个有关USB接口中传输数据的C语言源代码,对于通信方面的设计有很大的帮助

#include<main.h>
#include <stdio.h>
#include <avr/io.h>
#define usb_cmd (*(volatile unsigned char *)0xa001)
#define usb_data (*(volatile unsigned char *)0xa000) 
 /* 单片机的RAM有限,其中CH375子程序用512字节,剩余RAM部分可以用于文件读写缓冲 */
#define	CMD_RET_SUCCESS		0x51			/* 命令操作成功 */
#define FILE_DATA_BUF_LEN       0x0200  /* 外部RAM的文件数据缓冲区,缓冲区长度不小于一次读写的数据长度 */

#define CH375_INT_WIRE          ( PINB & 0x10 ) /* PINB.4, CH375的中断线INT#引脚,连接CH375的INT#引脚,用于查询中断状态 */
#define	CMD_SET_USB_MODE	0x15			/* 设置USB工作模式 */
#define	CMD_CHECK_EXIST		0x06			/* 测试工作状态 */
#define	CMD_RESET_ALL		0x05			/* 执行硬件复位 */
#define	CMD_GET_DESCR		0x46            /* 主机方式: 控制传输-获取描述符 */
#define	CMD_WR_USB_DATA7	0x2B			/* 向USB端点2的发送缓冲区写入数据块 */
#define	USB_INT_EP2_IN		0x0A			/* USB端点2的IN */
#define	CMD_GET_STATUS		0x22			/* 获取中断状态并取消中断请求 */
#define	CMD_UNLOCK_USB		0x23			/* 设备方式: 释放当前USB缓冲区 */
#define	USB_INT_DISCONNECT	0x16			/* 检测到USB设备断开事件 */
#define	CMD_DISK_INIT		0x51			/* 主机方式: 初始化USB存储器 */
#define	USB_INT_SUCCESS		0x14			/* USB事务或者传输操作成功 */
#define	CMD_DISK_SIZE		0x53			/* 主机方式: 获取USB存储器的容量*/ 
#define	CMD_RD_USB_DATA		0x28			/* 从当前USB中断的端点缓冲区读取数据块, 并释放缓冲区 */
#define	CMD_DISK_READ		0x54			/* 主机方式: 从USB存储器读数据块(以扇区512字节为单位) */
#define	CMD_DISK_RD_GO		0x55			/* 主机方式: 继续执行USB存储器的读操作 */
#define	USB_INT_DISK_READ	0x1D			/* USB存储器读数据块, 请求数据读出 */

unsigned int WordSwap(unsigned int input);
unsigned int LSwapINT16(unsigned short dData1,unsigned short dData2);
unsigned long LSwapINT32(unsigned long dData1,unsigned long dData2,unsigned long dData3,unsigned long dData4);
unsigned char ch375_init( unsigned char mode);
unsigned char set_usb_mode( unsigned char mode );
void usb_send_data(unsigned char *pbuff,unsigned int len);
unsigned char EnumMassDev(void);
unsigned char InitDisk(void);
unsigned char  ReadSector(unsigned long iLbaStart, unsigned char iSectorCount,unsigned char *oDataBuffer);
unsigned char  WriteSector(unsigned long iLbaStart, unsigned char iSectorCount,unsigned char *oDataBuffer);
unsigned char usb_rec_buff[64];
unsigned char usb_rec_buflen;
unsigned char diskbuff[512*2];
unsigned char  CH375_WR_CMD_PORT( unsigned char  type);
unsigned char  CH375_WR_DAT_PORT(unsigned  char type);


 
void main(void)
{
  void delayms( unsigned char  m) 
  { 
  unsigned char i,j; 
  while(m--)
  {for ( i = 100; i != 0; i -- )
  for ( j=10; j!=0; j-- );}
  }
  
 void delay2us(unsigned char  m) 
  { 
  unsigned char i; 
  while(m--)
  {for ( i = 2; i != 0; i -- );}
  }
 
 
 /* 设置CH375的工作模式 */
unsigned char set_usb_mode( unsigned char mode )
{
				   unsigned char i;
				   unsigned char RD_Data;

				   usb_cmd=CMD_SET_USB_MODE;
				  delay2us(1);

				   usb_data=0x06;
                    delay2us(1);
				    
                     for ( i = 100; i != 0; i -- )  /* 等待设置模式操作完成,不超过30uS */
				   		{
						 RD_Data=usb_data;
						if( RD_Data == CMD_RET_SUCCESS )
						return 1;
						}  /* 成功 */
						return 0;
}

unsigned char ch375_init(unsigned char mode)
{
	 unsigned char i, k;
	 
	 EIMSK|=0x10;
     /* 测试CH375是否正常工作 */
	 for( k=100; k!=0; k-- )
	   {
		usb_cmd=CMD_CHECK_EXIST ;  /* 测试CH375是否正常工作 */
		delay2us(1);
		usb_data=0x0f; /* 写入测试数据 */
	     /* 返回数据应该是测试数据取反 */
		 delay2us(1);
		i=usb_data;
	    if ( 0xf0!= i)   /* CH375不正常 */
	    {
		    for ( i=5; i!=0; i-- )
			  usb_cmd=CMD_RESET_ALL;  /* 多次重复发命令,执行硬件复位 */
			
            delayms(50);  /* 延时50ms */
	    }
		else
        break;
	 }
	 
     /* 设置CH375的工作模式 */
	   
  return set_usb_mode(mode); //内部固件模式
  }
 
void CtrlGetDescr( unsigned char type )
 {  /* 执行控制传输: 获取USB 描述符 */
 char IntStatus = 0; /* 清中断状态 */
CH375_WR_CMD_PORT(CMD_GET_DESCR); /* 控制传输-获取描述符 */
CH375_WR_DAT_PORT( type ); /* 0:设备描述符, 1:配置描述符 */
while ( IntStatus == 0 ); /* 等待操作完成，IntStatus 由中断服务程序更新 */
}


unsigned char get_ver(void)
{  unsigned char ver;
    usb_cmd=0x01;
	ver=usb_data;
    return ver;	
}

void _usb_send(unsigned char *pbuff,unsigned char len)
{    
     unsigned char i,status;
   	 usb_cmd=CMD_WR_USB_DATA7;
	 delay2us(3);
	
	 
	 usb_data=len;
	 
	 delay2us(1);
     for(i=0;i<len;i++)
	 { 
	    usb_data=pbuff[i];
		delay2us(1);
	 }
	while(status!=USB_INT_EP2_IN)
	{   
    usb_cmd=CMD_GET_STATUS;
    delay2us(3);

    status=usb_data;
	delay2us(3);
	
	}
}

void usb_send_data(unsigned char *pbuff,unsigned int len)
{    
     unsigned char i,r,n;
     EIMSK&=~0x10;
	  r=len/64;
	  n=len%64;
	  for(i=0;i<r;i++)
	  _usb_send((pbuff+i*64),64);
	  _usb_send((pbuff+i*64),n);
	
	 usb_cmd=CMD_UNLOCK_USB;
	 delay2us(1);
     EIMSK|=0x10;
	
}

unsigned char waitint(void)
{ 
  while(PINE&0x10);
  usb_cmd=CMD_GET_STATUS;
  delay2us(2);
  
  return usb_data;
  
}
unsigned char InitDisk(void)
{ 
   unsigned char status;
   usb_cmd=CMD_GET_STATUS;
   delay2us(10);
   status=usb_data;
   if (status==USB_INT_DISCONNECT) return status;//usb断开
   usb_cmd=CMD_DISK_INIT;
   status=waitint();
   if (status!=USB_INT_SUCCESS) return status;
   usb_cmd=CMD_DISK_SIZE;
   status=waitint();
   if (status!=USB_INT_SUCCESS) 
   {
      delayms(250);
	  usb_cmd=CMD_DISK_SIZE;
      status=waitint();   
   }
    if (status!=USB_INT_SUCCESS) return status;
	return 1;//u盘初始化成功
}

unsigned char  ReadSector(unsigned long iLbaStart, unsigned char iSectorCount,unsigned char *oDataBuffer) 
{
  unsigned int  mBlockCount;
  unsigned char  c;
  usb_cmd=CMD_DISK_READ;  /* 从USB存储器读数据块 */

  delay2us(10);
  usb_data=(unsigned char)iLbaStart;  /* LBA的最低8位 */
  delay2us(2);
  usb_data=(unsigned char)(iLbaStart >> 8);
   delay2us(2);
  usb_data=(unsigned char)(iLbaStart>> 16);
   delay2us(2);
  usb_data=(unsigned char)(iLbaStart>> 24); /* LBA的最高8位 */
   delay2us(2);
   usb_data=iSectorCount ;  /* 扇区数 */
  for ( mBlockCount = iSectorCount * 8; mBlockCount != 0; mBlockCount -- ) 
  {
       c = waitint();  /* 等待中断并获取状态 */
     if ( c == USB_INT_DISK_READ ) 
    	 {  /* 等待中断并获取状态,请求数据读出 */
         usb_cmd=CMD_RD_USB_DATA;  /* 从CH375缓冲区读取数据块 */
	       delay2us(10);
         c =usb_data;  /* 后续数据的长度 */
	       delay2us(2);
         while ( c -- ) 
     	  {
	     *oDataBuffer++ = usb_data;
	     delay2us(2);
	      }
         usb_cmd=CMD_DISK_RD_GO;  /* 继续执行USB存储器的读操作 */
       }
    else break;  /* 返回错误状态 */
  }
  if ( mBlockCount == 0 )
  {
    c = waitint();  /* 等待中断并获取状态 */
    if ( c== USB_INT_SUCCESS ) return( 1 );  /* 操作成功 */
  }
  return( c );  /* 操作失败 */
}

unsigned int WordSwap(unsigned int input)
{
	return(((input&0x00FF)<<8)|((input&0xFF00)>>8));
}



unsigned int LSwapINT16(unsigned short dData1,unsigned short dData2)
{
    unsigned int  dData;
    dData = ((dData2<<8)&0xff00)|(dData1&0x00ff);
	return dData;
}	

unsigned long LSwapINT32(unsigned long dData1,unsigned long dData2,unsigned long dData3,unsigned long dData4)
{
    unsigned long  dData;
    dData = ((dData4<<24)&0xff000000)|((dData3<<16)&0xff0000)|((dData2<<8)&0xff00)|(dData1&0xff);
	return dData;
}

}